Julian Lennon made a strong move toward establishing his own identity during his Washington debut at Constitution Hall last night. It must not be easy to both look and sound like your father, particularly when your father was John Lennon.

And there's no use decrying resemblances: familiar echoes run rampant in Julian's delivery, from the languid phrasing and easy falsetto to the timbre of his voice and the sweetly pungent edge of the music. He's going to carry that weight a long time, but judging from the sellout crowd's enraptured reaction to Lennon's stepping on stage, and its genuine excitement over his delivery, it's apparent that this 21-year-old has both the tools and the charisma to carve out his own niche in popular music.

If familial echoes worked against Lennon on his cautiously produced debut album, "Valotte," they were thankfully recast in live performance. Powered by Justin Clayton and Carlton Morales' twin lead guitars and a relentless rhythm section, the band's attack was much closer to gritty hard rock than the polished pop of the studio. Songs that seemed light on the album gained depth and conviction in their emboldened versions. And Lennon's singing, a bit unsure at the start, seemed to gain power as he sailed into his hits -- "Valotte," "Well I Don't Know" and "Too Late for Goodbyes." What he lacks in range and dynamics, he compensates for with youthful ebulliance.

Because he is virtually a novice, and one with a limited repertoire at that, Lennon ended up performing his entire album, filling out an hour-long show with an uninspired reading of Ben E. King's "Stand By Me," a plodding new blues-tinged rocker titled "Big Mama" and a rave-up encore that included a roundhouse version of "Day Tripper." As time goes by, Lennon may feel more comfortable performing songs associated with his father and his father's old band, but right now, one can't blame him for treading hallowed ground with caution.

It's way too early to judge Lennon as a songwriter, but in his best moments he manages to suggest a Beatlish intelligence filtered through more raucous and modernist energies. "Let Me Be" and "Vallotte" coursed with Lennon-McCartney graces; then again, the languid "Space" recalled Pink Floyd.

And perhaps because of the newness of it all, Lennon managed in his stage presence to be both awkward and ingratiating. If he is to the manner born, he is still to the stage unsure: Continued ecstatic audience reactions will go a long way to solving that problem. All in all, last night's performance was rewarding as much for its promise as for what it actually delivered.